A car safety belt is a safety device for use in protecting a driver or a passenger from abrupt jolts by restraining the forward motion of inertia of the driver or the passenger. The anchored straps of the safety belt, which buckle accross the chest and the hip, bring about a reduction in the speed of the forward motion of inertia of the driver's body or the passenger's body. In the meantime, the neck of the driver or the passenger is being exerted on by a force that is needed to reduce the speed of the motion of the neck. The force is directly proportional to the quantity of the reduced speed. As a result, the safety of the driver or the passenger can be further enhanced by lowering the rate of the reduced speed, which in turn lessens the force exerting on the neck of the driver or the passenger.